title: Reduction of histamine H1 receptor binding induced by high-fat diet can be prevented by DHA and dietary fiber in specific brain areas of male rats.
abstract: High-fat (HF) diet and obesity are risk factors for a number of mental health problems including depression, cognitive dysfunction, dementia, and neurodegenerative diseases. Histamine H1 receptors (H1Rs) are involved in many of these conditions. This study examined H1R receptor binding density in the brain of male rats fed a high-saturated fat (HF) diet, as well as the effect of docosahexaenoic acid (DHA), galacto-oligosaccharide (GOS) and resistant starch (RS) supplementation of HF diet. Alterations of H1R expression in the post-mortem rat brain were detected by [(3)H]-pyrilamine binding autoradiography. We found that HF diet significantly decreased H1R binding densities in the substantia nigra (SN), caudate putamen (CPu), hypothalamic arcuate nucleus (Arc), ventral tegmental area (VTA), piriform cortex (Pir) and primary motor cortex (M1), compared with low-fat fed rats, and the suppression of receptor binding density ranged from 31% to 48%. Interestingly, supplementing the HF diet with 0.5% n-3 polyunsaturated docosahexaenoic acid (DHA) prevented reduction of H1R binding densities in the SN and CPu. Addition of galacto-oligosaccharide (GOS) and resistant starch (RS) to the diet blunted HF induced reduction of H1R ligand binding in the SN and Pir, respectively. In conclusion this study showed that HF diet can alter H1R binding densities in various brain regions, and many of these changes can be prevented by adding DHA, GOS or RS to the diet.
authors.affiliation: Center for Translational Neuroscience, Illawarra Health and Medical Research Institute, School of Health Sciences, University of Wollongong, NSW 2522, Australia.
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Wu
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Yu
authors.forename: Yizhen
authors.initials: Y
authors.lastname: Wu
authors.forename: Craig
authors.initials: C
authors.lastname: Patch
authors.forename: Alexander
authors.initials: A
authors.lastname: Szabo
authors.forename: Xu-Feng
authors.initials: XF
authors.lastname: Huang
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D059305:Diet, High-Fat; D004043:Dietary Fiber / Q000494:pharmacology*; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D008297:Male; D011877:Radionuclide Imaging; D051381:Rats; D017208:Rats, Wistar; D011969:Receptors, Histamine H1 / Q000378:metabolism*
chemical_list: D004043:Dietary Fiber; D011969:Receptors, Histamine H1; D004281:Docosahexaenoic Acids
keywords: Docosahexaenoic acid; Galacto-oligosaccharide; Histamine H1 receptor; Receptor autoradiography; Resistant starch